Abstract: In recent years, the industry of wearable devices for pregnant women has been developing rapidly. Devices, ranging from fetal monitors to multi-functional health examination instruments, help in monitoring and managing maternal health indicators, such as fetal heart rate, blood glucose, and blood pressure, in and outside the hospital. Hospitals, maternal women and fetuses are bounded together by wearable devices for pregnant women in an unprecedented way. This article introduces wearable devices and their key technologies, and also investigates classical applications of such devices for pregnant women and the monitoring and management modes for the obstetrics department in the hospital. Finally, current major issues have also been analysed, with which we propose the way to deal.